// sendAppend sends RRPC, with entries to the given peer.
func (r *raft) sendAppend(to uint64) {
pr := r.prs[to]
if pr.isPaused() {
return
}
m := pb.Message{}
m.To = to
term, errt := r.raftLog.term(pr.Next - 1)
ents, erre := r.raftLog.entries(pr.Next, r.maxMsgSize)
if errt != nil || erre != nil { // send snapshot if we failed to get term or entries
m.Type = pb.MsgSnap
snapshot, err := r.raftLog.snapshot()
if err != nil {
panic(err) // TODO(bdarnell)
}
if IsEmptySnap(snapshot) {
panic("need non-empty snapshot")
}
m.Snapshot = snapshot
sindex, sterm := snapshot.Metadata.Index, snapshot.Metadata.Term
raftLogger.Debugf("%x [firstindex: %d, commit: %d] sent snapshot[index: %d, term: %d] to %x [%s]",
r.id, r.raftLog.firstIndex(), r.Commit, sindex, sterm, to, pr)
pr.becomeSnapshot(sindex)
raftLogger.Debugf("%x paused sending replication messages to %x [%s]", r.id, to, pr)
} else {
m.Type = pb.MsgApp
m.Index = pr.Next - 1
m.LogTerm = term
m.Entries = ents
m.Commit = r.raftLog.committed
if n := len(m.Entries); n != 0 {
switch pr.State {
// optimistically increase the next when in ProgressStateReplicate
case ProgressStateReplicate:
last := m.Entries[n-1].Index
pr.optimisticUpdate(last)
pr.ins.add(last)
case ProgressStateProbe:
pr.pause()
default:
raftLogger.Panicf("%x is sending append in unhandled state %s", r.id, pr.State)
}
}
}
r.send(m)
}
// sendAppend sends RRPC, with entries to the given peer.
func (r *raft) sendAppend(to uint64) {
pr := r.prs[to]
if pr.shouldWait() {
return
}
m := pb.Message{}
m.To = to
if r.needSnapshot(pr.Next) {
m.Type = pb.MsgSnap
snapshot, err := r.raftLog.snapshot()
if err != nil {
panic(err) // TODO(bdarnell)
}
if IsEmptySnap(snapshot) {
panic("need non-empty snapshot")
}
m.Snapshot = snapshot
sindex, sterm := snapshot.Metadata.Index, snapshot.Metadata.Term
log.Printf("raft: %x [firstindex: %d, commit: %d] sent snapshot[index: %d, term: %d] to %x [%s]",
r.id, r.raftLog.firstIndex(), r.Commit, sindex, sterm, to, pr)
pr.waitSet(r.electionTimeout)
} else {
m.Type = pb.MsgApp
m.Index = pr.Next - 1
m.LogTerm = r.raftLog.term(pr.Next - 1)
m.Entries = r.raftLog.entries(pr.Next)
m.Commit = r.raftLog.committed
// optimistically increase the next if the follower
// has been matched.
if n := len(m.Entries); pr.Match != 0 && n != 0 {
pr.optimisticUpdate(m.Entries[n-1].Index)
} else if pr.Match == 0 {
// TODO (xiangli): better way to find out if the follower is in good path or not
// a follower might be in bad path even if match != 0, since we optimistically
// increase the next.
pr.waitSet(r.heartbeatTimeout)
}
}
r.send(m)
}